Title:Electron and Positron solar modulation and prediction for AMS-02

Abstract: The solar modulation, a combination of diffusion, convection, magnetic drift
and energy loss inside the heliosphere is usually seen as a depletion in the
Galactic cosmic ray (CR) flux at low energy (less than 10 GeV/nuc).
Antiparticles such as antiprotons or positrons undergo the same processes of
respective particles but with a different magnitude depending on the Solar
magnetic field polarity. For electrons and positrons, due to the small mass,
energy loss mechanisms as inverse compton, synchrotron, bremsstrahlung and
ionization have to be taken into account, together with the typical adiabatic
losses considered in the heliosphere. We developed a Monte Carlo stochastic
simulation with the aim to compare the solar modulation of particles and
antiparticles in the same observation period. We are able to estimate the
different behaviours associated to the charge sign dependent processes of the
heliospheric modulation. We compared the simulated positron fraction with
measurements performed by AMS-01 and PAMELA. We also present the prediction for
the AMS-02 experiment.

Comments:

Accepted for publication in the Proceedings of the ICATPP Conference on Cosmic Rays for Particle and Astroparticle Physics, Villa Olmo (Como, Italy), 7--8 October, 2010, to be published by World Scientific